A reading order for stories occurring prior to or parallel to X-Men #1 in September 1963. A part of Crushing Comics’ Guide to Marvel Comics. Last updated September 2018.
What does Era #0: Before The X-Men include?
This era of the X-Men Reading Order is focused on X-Men pre-history – stories retroactively inserted into the period prior to X-Men #1 in 1963. That mostly consists of Wolverine stories, since he has the most (and most interesting) history to dig through.
You could optionally read Namor’s Golden Age, Invaders, and Atlas Era stories in this period as well, if you choose to include him in your X-Men read.